Paspalum is a large genus of warm-season grasses in the family Poaceae (subfamily Panicoideae, tribe Paspaleae), comprising roughly 400–585 species depending on the treatment applied. Named by Carl Linnaeus and published in 1759, the genus is commonly known as finger-grasses, a name that references the characteristic spikelike racemes that radiate finger-like from the stem apex. The type species is Paspalum dimidiatum.
Plants in this genus are annual or perennial, and may be cespitose, rhizomatous, or stoloniferous. Culm height ranges enormously across the genus — from just 3 cm in diminutive species to 400 cm in the tallest — and growth habit spans from erect to prostrate. The spikelets are plano-convex and arranged in two rows along flattened branch axes, a diagnostic feature of the genus.
Paspalum is most diverse in subtropical and tropical regions and occurs widely across the Americas, Africa, Asia, and Australia. Species occupy a broad range of habitats, from seasonally flooded wetlands and coastal areas to upland grasslands and disturbed ground. As C4 grasses, they are adapted to high-light, warm-temperature environments and can tolerate periodic drought, salinity, or waterlogging depending on the species.
The genus has significant economic importance. Bahiagrass (P. notatum) is a major forage and low-maintenance turf grass across warm-temperate regions. Seashore paspalum (P. vaginatum) is prized for its tolerance of salt and reclaimed water, making it a preferred turf species for coastal golf courses and sports fields. Kodo millet (P. scrobiculatum) has been cultivated for centuries in South and Southeast Asia as a drought-hardy grain crop. Some species, however, are serious pasture weeds or invasive threats, and the ergot fungus Claviceps paspali causes neurological poisoning ("paspalum staggers") in livestock that graze contaminated seed heads.
Distribution
Paspalum is distributed widely across tropical and warm-temperate regions globally, with its center of diversity in the Americas. The genus is documented across much of South and Central America, North America (with over 50 species recorded in the southwestern US alone), Africa, Asia, and Australia. Within the Americas, species occupy habitats from sea level coastal zones to montane grasslands. Globally, the genus is most species-rich in subtropical latitudes, where warm temperatures and seasonal rainfall support diverse growth forms from wetland margins to dry upland grasslands.
Ecology
Paspalum grasses are C4 photosynthesizers, giving them a competitive advantage in hot, high-light environments. The genus spans a wide ecological amplitude: some species are strictly aquatic or semi-aquatic wetland plants, others colonize coastal sands and tolerate salinity, and still others thrive in disturbed upland grasslands. Growth forms — tufted, stoloniferous, or rhizomatous — reflect adaptations to different disturbance and moisture regimes.
The genus has important ecological interactions. Seeds are consumed by granivorous birds, and foliage serves as host material for various moth and butterfly caterpillars. A significant negative interaction involves the ergot fungus Claviceps paspali, which infects Paspalum seed heads and produces alkaloids that cause "paspalum staggers," a neurological disorder in cattle, sheep, and horses that graze contaminated pastures.
Cultivation
Several Paspalum species are cultivated for forage, turf, and grain. Bahiagrass (P. notatum) is widely grown across warm-temperate and subtropical pastures, valued for its drought tolerance, persistence under heavy grazing, and compatibility with companion legume crops. Seashore paspalum (P. vaginatum) has become the turf grass of choice for coastal and arid-region golf courses and sports venues because it tolerates brackish irrigation water and even treated greywater. Kodo millet (P. scrobiculatum) is cultivated as a grain crop in South and Southeast Asia, particularly in dry, marginal areas where other cereals perform poorly.
Cultural Uses
Kodo millet (Paspalum scrobiculatum) has a long history of cultivation as a subsistence and minor commercial grain crop across India, Nepal, and parts of Southeast Asia, providing food security in drought-prone dryland farming systems. Seashore paspalum (P. vaginatum) has gained wide adoption in sports turf management globally, with elite cultivars used on golf courses, soccer pitches, and major league baseball fields. Several Paspalum species contribute to pastoral economies in South America and Africa as components of natural and sown pasture systems.
Conservation
Some Paspalum species have become significant environmental weeds outside their native ranges. Paspalum quadrifarium (tussock paspalum) is listed as a noxious weed in Australia, where dense stands outcompete native vegetation. Paspalum dilatatum (dallisgrass) is widely naturalized as a pasture weed and lawn pest across Australia and other warm-temperate regions. The broad invasive potential of certain species across the genus warrants monitoring in regions where introduced populations are expanding.
Taxonomy Notes
Paspalum L. was formally described by Carl Linnaeus in 1759 (Syst. Nat. ed. 10. 2: 855). It is placed in the family Poaceae, subfamily Panicoideae, tribe Paspaleae, with the type species Paspalum dimidiatum. The genus has full accepted taxonomic status. Species counts vary considerably between authorities: GBIF recognizes 585 taxa while some older regional treatments list approximately 250 species, reflecting ongoing revision of species boundaries within this complex group.
